There has previously been developed a number of different types of breathing equipment for respiration protection during stays for a shorter or longer time in a contaminated atmosphere. Most of this equipment has been developed for professional effort in the fighting of fires or the like. One achieves an efficient protection, but the size, weight, price, etc. make the equipment unsuitable as a general "escape equipment". An escape equipment should be able to find room in a little bag, be operative at short notice, and give an efficient respiration protection for approximately 10 minutes. In spite of the fact that the need for such an equipment undoubtedly is great, there is--as far as one knows--no commercially available equipment which satisfies these requirements.
From U.S. Pat. No. 4,552,140 there is known a transparent impervious flexible hood for placing over the head of a user and which is sealingly affixed to an inflatable collar. An annular saddle-shaped reservoir contains a supply of pressurized oxygen gas and is concentrically positioned on the collar, so that when this is inflated the weight of the reservoir seals the collar around the neck of the user. A control mechanism is actuatable by the user for the supply of oxygen gas for simultaneously filling the hood and inflating the collar. In the hood there is also arranged a CO.sub.2 absorber for purifying exhaled gas, and an ejector means is provided for guiding the breathing gas through the absorber so that the gas may be recirculated.